Initial management of hypertensive emergencies and urgencies in children

INTRODUCTION — This topic discusses the initial management of hypertensive emergencies and urgencies in children. The diagnostic evaluation of acute severe hypertension in children is discussed separately. (See "Approach to hypertensive emergencies and urgencies in children".)

DEFINITION — Acute severe hypertension has traditionally been divided into hypertensive emergencies and hypertensive urgencies. However, any classification scheme that divides the clinical presentation of patients with acute severe hypertension into separate categories is by nature arbitrary [1,2]. Clinical judgment must be used to gauge the severity of hypertension and guide management.

While there is no specific numerical value or blood pressure (BP) percentile that identifies "acute severe hypertension" in children and adolescents, in one relatively large case series of pediatric patients with severe hypertension, most patients had BP readings well in excess of stage 2 hypertension (table 1) [3]. The 2017 American Academy of Pediatrics Clinical Practice Guideline on childhood hypertension suggests that clinicians become concerned about acute target-organ damage when the patient's BP exceeds 30 mmHg above the 95^th percentile for sex, age, and height (figure 1A-B and table 2 and table 3) [4].

The classification of BP in infants, children, and adolescents is discussed in detail separately. (See "Definition and diagnosis of hypertension in children and adolescents", section on 'Definitions' and "Evaluation and diagnosis of hypertension in infants between one month and one year of age", section on 'Normal blood pressure' and "Etiology, clinical features, and diagnosis of neonatal hypertension", section on 'Normal blood pressure'.)

Hypertensive emergency — An acute severe symptomatic elevation in BP with evidence of potentially life-threatening symptoms or target-organ damage (eg, hypertensive encephalopathy, heart failure, or acute kidney injury) defines a hypertensive emergency [5-7]. BPs are commonly elevated far above the level of stage 2 hypertension (table 1). Patients with a hypertensive emergency warrant rapid assessment to exclude conditions that might alter BP management followed by emergency administration of intravenous (IV) antihypertensive agents to rapidly lower BP (algorithm 1).

The presence or absence of symptoms or target organ damage is more important than the absolute BP level. For example, a child with chronic hypertension may have impressively high BP measurements without symptoms. Another child with an acute rise in BP may manifest a hypertensive emergency despite a BP that seems to be only moderately elevated.

Hypertensive urgency — An acute severe elevation in BP without life-threatening symptoms or evidence of acute target-organ damage describes a hypertensive urgency [5-7]. A child with hypertensive urgency warrants a prompt evaluation. The duration of hypertension (acute or chronic) is an important determinant of intervention (algorithm 2). (See 'Hypertensive urgency' below.)

EVALUATION — The evaluation of children with hypertensive emergencies, which includes the recognition of signs of target-organ damage and identification of underlying conditions that alter blood pressure (BP) management, is discussed in greater detail separately. (See "Approach to hypertensive emergencies and urgencies in children".)

INITIAL MANAGEMENT — The initial management is determined by the presence of a hypertensive emergency with life-threatening symptoms or target-organ damage (algorithm 1) or a hypertensive urgency (algorithm 2) [1,2,6-11]. Knowledge of the most prevalent etiologies by age group also helps to guide treatment decisions (table 4). (See "Approach to hypertensive emergencies and urgencies in children" and 'Conditions that alter initial treatment' below.)

Initial stabilization — While the presence of severe hypertension is being confirmed, the patient should be placed in a treatment area that can support critical care functions and monitoring. Treatment includes:

●Establish continuous cardiorespiratory monitoring, including pulse oximetry.

●Support the airway and breathing as needed while confirming and monitoring the BP. Medications that might increase BP (eg, ketamine) should be avoided during rapid sequence intubation. (See "Rapid sequence intubation (RSI) in children for emergency medicine: Approach".)

●For patients with hypertensive emergencies (acute severe symptomatic elevation in BP with evidence of potentially life-threatening symptoms or target-organ damage), establish intravenous (IV) access consisting of two IV lines, whenever possible. One IV line should be dedicated to administration of antihypertensive medications. Initial laboratory studies should be obtained, if not already available (table 5). (See "Approach to hypertensive emergencies and urgencies in children", section on 'Ancillary studies'.)

Measure BP frequently: either automated/oscillometric or ausculatory BP measurements every one to two minutes or, if possible, intra-arterial BP measurement. However, treatment should not be delayed to obtain arterial cannulation. Frequently repeated BP measurement by means of auscultation or an automatic oscillometric BP device may suffice during initial care, with invasive monitoring established later. (See 'Confirmation of severe hypertension' below.)

●Seizures, if present, should be treated with anticonvulsants such as lorazepam (initial dose: 0.05 to 0.1 mg/kg) until seizures stop. (See "Management of convulsive status epilepticus in children".)

●Patients with papilledema, altered mental status, seizures, or neurologic deficits on physical examination should undergo emergency neuroimaging.

Confirmation of severe hypertension — Once severe hypertension is discovered, the BP should be confirmed with an appropriate cuff, preferably using auscultation. Too small of a cuff will artificially elevate the BP reading (figure 2). Patients who newly present with acute hypertension should also have BP taken in both arms and at least one leg; a lower extremity BP that is less than upper extremity BP suggests coarctation of the aorta. If manual BP measurement is not possible in the emergency situation, automated BP readings may be substituted; the same guidance regarding cuff size should be followed. (See "Definition and diagnosis of hypertension in children and adolescents", section on 'Technique of blood pressure measurement'.)

If repeated measurements confirm the BP elevation, a focused history and physical examination should be performed to identify evidence of end-organ damage (eg, hypertensive encephalopathy, heart failure, or renal disease). An acute severe elevation in BP with life-threatening symptoms (eg, respiratory distress, altered mental status, or seizures) or evidence of acute target-organ damage defines a hypertensive emergency and, after exclusion of conditions that alter initial BP management, warrants emergency lowering of BP using IV therapy. (See "Approach to hypertensive emergencies and urgencies in children", section on 'Identify conditions that alter initial blood pressure management'.)

Hypertensive emergency

Blood pressure goal — The ultimate goal for treatment is achievement of a systolic BP value that will promote resolution of life-threatening signs and symptoms and prevent further hypertensive target-organ damage. Generally speaking, this is typically a systolic BP at the 95^th percentile for age, sex, and height (table 2 and table 3) for children less than 13 years of age and BP <130/80 for adolescents, but the goal should be individualized for each patient as determined by response to treatment and, if known, the underlying cause. Whenever possible, obtain emergency consultation with a physician who has expertise in managing severe pediatric hypertension.

For children with a hypertensive emergency, we suggest IV medication that, over the first eight hours of treatment, lowers systolic BP in a controlled fashion by no more than 25 percent of the difference between the current systolic BP and the goal systolic BP [1,4]. This approach is based upon expert opinion and experience. Overly rapid lowering of BP by more than 25 percent of the planned BP reduction in the first eight hours of treatment in patients with chronic hypertension can cause irreversible target-organ damage, including permanent neurologic sequelae, visual defects, myocardial infarction, and renal insufficiency due to autoregulatory responses in key circulatory beds such as the brain and kidneys [2,7,9,12].

Initial treatment — These treatment recommendations for hypertensive emergencies are based upon limited pediatric evidence from small observational studies and have been largely extrapolated from randomized controlled trials in adults (algorithm 1) [1]. Prior to treatment, it is necessary to identify conditions (eg, acute intracranial injury, intracranial mass lesion, uncorrected coarctation of the aorta, preeclampsia/eclampsia, severe pain, or sympathetic overactivity) for which antihypertensive treatment is contraindicated or may need modification. (See 'Conditions that alter initial treatment' below.)

Whenever possible, an experienced clinician such as a pediatric nephrologist or intensivist should guide therapy of pediatric hypertensive emergencies once emergency stabilization is accomplished. For children with hypertensive emergencies, we suggest IV labetalol or nicardipine rather than either hydralazine or sodium nitroprusside (table 6). Nicardipine is the preferred medication for the treatment of severe symptomatic hypertension in infants younger than one year of age, although labetalol is also widely used (see "Management of hypertension in neonates and infants", section on 'Severe symptomatic hypertension'). Labetalol may cause bronchoconstriction and may need to be avoided in infants with chronic lung disease or children with asthma. Labetalol may also worsen pulmonary edema in children with heart failure.

Both labetalol and nicardipine permit the rapid modification of treatment based upon patient response [1,2,8,11,13,14]:

●Labetalol is given as an initial bolus followed by a continuous IV infusion (preferred) or as repeated bolus doses every 10 minutes.

●Nicardipine is given as a continuous IV infusion. Bolus doses of 30 mcg/kg (up to 2 mg) of nicardipine, although not studied in children, are effective in adults and may be utilized in consultation with a pediatric nephrologist.

There is a wide range of dosing for continuous IV infusion of labetalol or nicardipine. In general, the clinician should start with the lowest dose of the range and adjust the infusion rate based upon BP response. Within the first eight hours of treatment, infusion rates should be titrated to achieve the desired BP reduction of no more than 25 percent of the total planned systolic BP reduction (difference between the current systolic BP and the goal systolic BP) while avoiding additional symptomatic BP increases. (See 'Blood pressure goal' above.)

Hydralazine and sodium nitroprusside have adverse effects that make them less suitable for the initial treatment of severe hypertension in children:

●Hydralazine is a direct vasodilator of arterial smooth muscle. Its onset of action is slower than nicardipine or labetalol, and its duration of action is longer than either of these agents. Overshoot hypotension with the potential for target-organ ischemia is also more likely with hydralazine [15].

●Sodium nitroprusside, previously a commonly used agent for acute severe hypertension, is less favored because of the potential for cyanide toxicity. Approximately one-fourth of children in a clinical trial of nitroprusside had elevated cyanide levels [1,16,17]. Impaired kidney function can increase the degree of cyanide accumulation [18]. Co-administration of thiosulfate can help mitigate cyanide toxicity in patients receiving sodium nitroprusside.

In addition to antihypertensive therapy, patients with underlying chronic kidney disease and volume overload may also warrant diuretic therapy (eg, IV furosemide or bumetanide) as part of the approach to their hypertension, but diuretics should never be used alone in such patients. Acute diuretic therapy may also be indicated in patients with hypertensive emergencies associated with congestive heart failure and pulmonary edema. (See "Heart failure in children: Management", section on 'Diuretics'.)

There is an urgent need for better information on pharmacologic management of severe hypertension in children, especially for some of the more commonly used IV antihypertensive medications, including hydralazine and labetalol. The lack of dosing recommendations based upon properly conducted pediatric clinical trials clearly hinders provision of safe, effective care to this vulnerable patient population.

Failure to respond to initial therapy — If initial therapy with continuous IV infusion of labetalol or nicardipine fails to reduce the BP within 30 minutes, then we suggest escalation of therapy to continuous infusions of both labetalol (if not contraindicated) and nicardipine (table 6).

If the patient has contraindications to labetalol or if BP is not lowered after a second 30 minutes of treatment with continuous infusions of both labetalol and nicardipine, then, for patients with no chronic kidney disease, continuous infusion of sodium nitroprusside is preferable to hydralazine because of its more rapid onset and shorter duration of action. To avoid excessive blood cyanide accumulation, patients with chronic kidney disease should be treated with hydralazine rather than sodium nitroprusside.

For patients receiving sodium nitroprusside, monitoring of cyanide levels is performed and, whenever available, prophylactic administration of thiosulfate is warranted; dose and duration of sodium nitroprusside should also be limited. Patients unresponsive to labetalol, nicardipine, and sodium nitroprusside may receive hydralazine.

Other generally available IV medications that may be used for the management of hypertensive emergencies include esmolol and fenoldopam. Esmolol has a rapid onset and offset of action, which can be useful in certain patient populations, such as following cardiac surgery. Fenoldopam has not proven to be as potent as other IV antihypertensive medications and is more expensive than alternative agents. There has been interest in the ultra-short-acting IV calcium channel blocker clevidipine [19,20], but no controlled studies have been conducted in children. It is also more expensive than other established agents such as nicardipine or esmolol.

When diuretic therapy is ineffective for correcting fluid overload, dialysis is indicated. (See "Pediatric acute kidney injury: Indications, timing, and choice of modality for kidney replacement therapy".)

We recommend avoiding the IV angiotensin-converting enzyme inhibitor enalaprilat given the lack of established pediatric dosing and known tendency to cause acute kidney injury.

Hypertensive urgency — After initial stabilization and the exclusion of conditions that may alter initial BP therapy, the treatment goal for children with hypertensive urgencies depends upon the clinical situation. As in any hypertensive child, the ultimate goal would be a systolic BP <90^th percentile for age, sex, and height in children <13 years of age or <130/80 in adolescents ≥13 years of age (figure 1A-B and table 2 and table 3). However, a higher goal such as the 95^th percentile for age, sex, and height may be appropriate initially, especially if the child was not previously known to be hypertensive and was still undergoing diagnostic evaluation. (See "Nonemergent treatment of hypertension in children and adolescents", section on 'Target blood pressure goals'.)

Children newly presenting with a hypertensive urgency warrant careful evaluation to determine the underlying etiology, if any, and whether the hypertension is chronic or acute (algorithm 2):

●Acute onset – When the urgency arises from an acute process with a rapid change in mean arterial pressure (eg, acute glomerulonephritis), intervention should occur promptly (ie, within hours). For these children, we suggest IV bolus doses of labetalol (preferred) or, for infants younger than one year of age or for children with asthma, bolus IV doses of hydralazine or nicardipine (table 6). IV antihypertensive therapy may also be used if the patient is unable to take medications orally.

●Chronic condition – For children with chronic hypertension due to a known condition (eg, chronic kidney disease) in which BP has increased gradually over time, lowering of the BP should occur less quickly (eg, over one to two days or more).

•For patients who are able to take oral medication, we suggest oral isradipine or clonidine (table 7). Isradipine can be compounded into a stable liquid formulation for administration to infants and toddlers. If isradipine or clonidine are not available, other potential agents include oral hydralazine and minoxidil [21-24]. However, dosing of these agents is more difficult given the lack of stable suspension preparations.

Short-acting oral nifedipine is not recommended in children due to difficulties with dosing, prolonged and unpredictable action, risk of hypotension, and rebound hypertension [25]. The onset of action for other calcium channel blockers is too slow to recommend them for children with hypertensive urgencies.

•If the patient cannot take oral medications, then bolus doses of IV medications (labetalol [preferred], or, for infants younger than one year of age or for children with asthma, bolus IV doses of hydralazine or nicardipine) should be given to slowly lower the BP.

FURTHER MANAGEMENT — Once initial control of severe hypertension is achieved, plans should be made for further diagnostic evaluation and correction of any identifiable underlying cause in consultation with the appropriate pediatric subspecialist. (See "Evaluation of hypertension in children and adolescents".)

The amount of time needed for further blood pressure (BP) reduction after the initial eight hours of therapy will depend upon patient factors, including presumed duration of acute severe hypertension, required regimen to control BP, and underlying etiology; and should also be guided by an experienced clinician such as a pediatric nephrologist or intensivist. (See 'Initial treatment' above and 'Conditions that alter initial treatment' below.)

If an intravenous (IV) infusion was required to control the child's BP, gradual conversion to oral antihypertensive medications under the guidance of a specialist with expertise in treating pediatric hypertension, whenever possible, should be undertaken until definitive treatment can be arranged.

●Secondary hypertension – If the underlying cause cannot be corrected so that hypertension is abolished, or if hypertension persists after treatment, chronic pharmacologic therapy should be continued. The regimen depends upon the underlying cause of hypertension, physician comfort, and the presence of any comorbid conditions (eg, diabetes mellitus and/or kidney disease). (See "Nonemergent treatment of hypertension in children and adolescents", section on 'Choice of drug'.)

Nonpharmacologic measures (eg, salt restriction and weight control) should also be utilized in conjunction with antihypertensive medications in such patients. (See "Nonemergent treatment of hypertension in children and adolescents", section on 'Management approach'.)

●Primary hypertension – The patient with primary hypertension as the etiology of their acute severe hypertension should also receive both nonpharmacologic and pharmacologic therapy. Nonpharmacologic measures, if successfully adhered to by the patient, offer the possibility of eventual discontinuation of drug therapy, especially if obesity is a significant contributor to the BP elevation. (See "Nonemergent treatment of hypertension in children and adolescents", section on 'Management approach'.)

CONDITIONS THAT ALTER INITIAL TREATMENT

Intracranial hypertension — Blood pressure (BP) reduction is contraindicated in patients with intracranial hypertension, including children with serious intracranial injury, space-occupying brain lesions, or stroke. If a central nervous system condition is suspected or cannot be excluded based upon clinical findings, then emergency neuroimaging should be obtained prior to antihypertensive therapy. Treatment of elevated intracranial pressure is discussed separately. (See "Elevated intracranial pressure (ICP) in children: Management".)

Coarctation of the aorta — Classic findings of coarctation of the aorta are systolic hypertension in the right or both upper extremities, diminished or delayed femoral pulses (brachial-femoral delay), and low or unobtainable arterial BP in the lower extremities. (See "Clinical manifestations and diagnosis of coarctation of the aorta", section on 'Blood pressure and pulses'.)

Patients with uncorrected coarctation of the aorta warrant angioplasty or surgical repair. However, intravenous (IV) antihypertensive therapy may be needed following presentation, especially in older children and adolescents, until definitive treatment can be arranged. The general management of patients with coarctation of the aorta is discussed separately. (See "Management of coarctation of the aorta", section on 'Choice of intervention'.)

Severe pain — Children with severe pain should receive systemic analgesia (eg, fentanyl or morphine) with reassessment of BP after pain control.

Preeclampsia/eclampsia — Delivery of the fetus prevents progression of maternal hypertension and is the primary treatment for preeclampsia. Severe preeclampsia dictates delivery if the pregnancy is beyond 32 weeks gestation. The intrapartum and postpartum management of preeclampsia is discussed separately. (See "Preeclampsia: Antepartum management and timing of delivery".)

Women who have severe preeclampsia at less than 32 weeks require management at a tertiary care obstetrical center, which may include antihypertensive therapy. (See "Treatment of hypertension in pregnant and postpartum patients".)

Conditions with sympathetic overactivity — Patients whose acute severe hypertension arises from sympathetic overactivity warrant modification of treatment depending upon the underlying cause:

●Cocaine, amphetamine, or other sympathomimetic medication overdose – In patients presenting with a sympathomimetic overdose, hypertension is frequently transient, and many patients need no specific treatment. Benzodiazepines (eg, lorazepam or diazepam) are often effective in treating hypertension and agitation. Labetalol and other beta-adrenergic antagonists should be avoided because of the risk of causing unopposed alpha-adrenergic effects, which may exacerbate hypertension and lead to other cardiovascular complications. Rapid-acting IV medications with a short duration of effect such as phentolamine, sodium nitroprusside, or nitroglycerin are preferred. (See "Cocaine: Acute intoxication", section on 'Approach to management'.)

●Pheochromocytomas and paragangliomas – Patients who present acutely with severe hypertension from a pheochromocytoma or paraganglioma can be managed in the short term with any of the IV agents discussed above. Once BP has been stabilized, specific therapy with an alpha-blocking agent should be initiated pending surgical resection. (See "Pheochromocytoma and paraganglioma in children", section on 'Clinical presentation' and "Pheochromocytoma and paraganglioma in children", section on 'Treatment'.)

●Jellyfish sting (Irukandji syndrome) – Children stung by box jellyfish, which are capable of causing severe pain and hypertension (Irukandji syndrome) and are typically located in the Northern territories of Australia and the Indo-Pacific, require specific treatment of the sting site to inactivate nematocysts and parenteral pain medication. Those with persistent hypertension may also need IV infusions of phentolamine, sodium nitroprusside, or nitroglycerin. (See "Jellyfish stings", section on 'Irukandji syndrome (generalized pain and severe hypertension)'.)

●Scorpion sting – Children with severe hypertension following a scorpion sting warrant pain control, treatment of hypertension, and, for many scorpion species, antivenom. (See "Scorpion envenomation causing autonomic dysfunction (North Africa, Middle East, Asia, South America, and the Republic of Trinidad and Tobago)", section on 'Management'.)

SOCIETY GUIDELINE LINKS — Links to society and government-sponsored guidelines from selected countries and regions around the world are provided separately. (See "Society guideline links: Hypertensive emergencies and urgencies in children".)

SUMMARY AND RECOMMENDATIONS

●Whenever possible, an experienced clinician such as a pediatric nephrologist or intensivist should guide therapy of pediatric hypertensive emergencies once emergency stabilization is accomplished. Knowledge of the most prevalent etiologies by age group also helps guide medication decisions (table 4). (See "Approach to hypertensive emergencies and urgencies in children", section on 'Etiology of hypertensive emergency' and 'Conditions that alter initial treatment' above.)

●An acute severe elevation in blood pressure (BP) with severe, life-threatening symptoms and/or evidence of acute end-organ damage (eg, hypertensive encephalopathy, heart failure, or renal injury) establishes the presence of a hypertensive emergency. Clinicians should be most concerned about target-organ complications in patients with acute development of BP values >30 mmHg above the 95^th percentile for age, sex, and height (figure 1A-B and table 2 and table 3). The absolute level of BP elevation is less important than whether symptoms or evidence of target-organ damage are present. Hypertensive emergencies warrant initial management as described in the algorithm (algorithm 1). (See 'Definition' above and 'Initial management' above.)

●Prior to antihypertensive treatment, great care must be taken to identify conditions (eg, acute intracranial injury, intracranial mass lesion, uncorrected coarctation of the aorta, or sympathetic overactivity) for which antihypertensive treatment is contraindicated or may need modification in children with severe BP elevation. (See 'Conditions that alter initial treatment' above.)

●For children with hypertensive emergencies without conditions that alter initial treatment, we suggest emergency administration of intravenous (IV) labetalol or nicardipine rather than IV hydralazine or sodium nitroprusside (table 6) to lower systolic BP in a controlled fashion by no more than 25 percent of the difference between the current systolic BP and the goal systolic BP over the first eight hours of treatment (Grade 2C). (See 'Initial treatment' above and 'Conditions that alter initial treatment' above.)

●IV nicardipine is the preferred medication for the treatment of severe symptomatic hypertension in infants younger than one year of age and children with potential contraindications to labetalol (eg, patients with asthma or heart failure). (See 'Blood pressure goal' above and 'Initial treatment' above.)

●In addition to antihypertensive therapy, patients with underlying chronic kidney disease and volume overload or heart failure and pulmonary edema may also warrant diuretic therapy (eg, IV furosemide or bumetanide) as part of the approach to their hypertension, but diuretics should never be used alone in such patients. (See 'Initial treatment' above.)

●If initial therapy with continuous IV infusion of labetalol or nicardipine fails to reduce the BP within 30 minutes, therapy is escalated to continuous infusions of both labetalol (if not contraindicated) and nicardipine. (See 'Failure to respond to initial therapy' above.)

●An acute severe elevation in BP without severe, life-threatening symptoms and evidence of acute end-organ damage describes a hypertensive urgency. A child with a hypertensive urgency warrants a prompt evaluation (algorithm 2). (See 'Hypertensive urgency' above.)

●The treatment goal for children with hypertensive urgencies depends upon the clinical situation. The ultimate goal would be a BP <90^th percentile for age, sex, and height in children <13 years of age or <130/80 in adolescents ≥13 years of age. (See 'Hypertensive urgency' above.)

●For children with hypertensive urgencies who have a rapid rise in mean arterial BP associated with an acute condition (eg, acute glomerulonephritis), we suggest IV bolus doses of labetalol (preferred) or, for infants younger than one year of age or for children with contraindications to labetalol, IV bolus doses of hydralazine or nicardipine to lower BP over several hours (Grade 2C). (See 'Hypertensive urgency' above.)

●For children with chronic hypertension due to a known condition (eg, chronic kidney disease) in which BP has increased gradually over time, we suggest oral isradipine or, for older children and adolescents, clonidine to lower BP over several days (table 7) (Grade 2C). If the patient cannot take oral medications, then bolus doses of IV medications (labetalol [preferred], or, for infants younger than one year of age or for children with asthma, bolus IV doses of hydralazine or nicardipine) should be given to slowly lower the BP. (See 'Hypertensive urgency' above.)

●Once initial control of severe hypertension is achieved, plans should be made for further diagnostic evaluation and correction of any identifiable underlying cause in consultation with the appropriate pediatric subspecialist. (See 'Further management' above.)